This video series provides a fresh look at skill-transfer exercises and midline stability, combining the powers of Kelly Starrett and gymnast Carl Paoli. Both San Francisco CrossFit coaches add their expertise to refine basic CrossFit movements with the aim of improving power output.

“The goal is to take the very basic things that we do that are simple to see and understand and then translate them into the fun stuff,” Paoli says.

According to Starrett, the easiest way to express midline stability, defined as “The Position,” is straight up and down, so a double-under is a perfect starting place. Paoli demonstrates the body position and power of an integrated double-under.

“If we focus on body position, body mechanics, in some of these kind of more throw-away, simple body exercises, we can really lay a foundation and create an opportunity to make those things skill-transfer exercises,” Starrett says.

OMG- This is it. I've been hoping forever for this vid to come out so I can finally get some clarification on the hollow body position and how that relates to keeping the lumbar curve intact during squatting and deadlifting. Hury up already with part 2.

I'm looking forward to seeing how the 'neutral position' applies to deadlifts or squats, having torn up my lower back about two months ago.
It was a heavy set of 5 squats, and I was trying not to 'overextend' as K-Star would say here or in his MWOD pieces, but something was lost in the translation. I had lost my lumbar curve and was hobbling as a result.

I'm fine now, but I'm back to 'bowing up' my chest: ten gallons of air on the inhale and my ribs out, to protect the lumbar curve. It might be an 'energy loss' position, but it's a safe position at this point.

These are my favorite two contributors to the CFJ but I still dont get the obsession with double unders in Crossfit. Every other movement in Crossfit you can relate to something in real life but it seems like DUs are a method to test capacity and not a functional movement. I dont get the love affair with DUs, maybe its just me...

@Tim. I suppose you could ask a boxer the same question. Buddy Lee said to be fast you have to train fast. Doubles are excellent for testing coordination and being able to think clearly in a stressful situation. It's also a really effective conditioning tool. Try max doubles in 5 minutes and you may understand what I mean. It's also an easy way to separate people. Just look at main page every time a workout with doubles is posted. You see endless comments and subs just because people want to have a good time. I mean Tuck Jumps? You really can't compare those to double unders at all.

My honest question is why do we stop there? What about triples or crossovers? What about doing reverse doubles?

Also, excellent video. Without Starret we would all be broken hobbly old men.

The double under may not seem 'functional' since it doesn't 'happen in real life' in that exact portrayal of the movement. The same could be said for something like a Turkish get-up; I have seldom needed to hold an object with my arm straight out and get up off of the floor. Most of us in 'real life' would gently put the object down, stand up, and then safely deadlift or clean the object so that we could carry it. Does that make the TGU a 'non-functional' movement? No. The TGU does a lot for teaching us how to move better, as well as express overall body strength.

The double under has many things that are great about it:

1. Conditioning. Someone said to do 5 minutes of max double unders. Try doing this in various amounts of times or in interval style training for 2 weeks, and see what impact it has on your stamina, endurance, and work capacity. If it didn't help at all with your conditioning, I would be amazed.

2. Foot speed. Read Greg Amundson's article on the CFJ titled something like 'The Chink in my Armor'. He talks about how DUs were his weakness, but when he finally tackled them and became better at them, he was much quicker on his feet. This is just one reason why those involved in any of the martial arts employ jump rope in their overall training.

3. Hand speed. Various sports applications for having a wrist that is stronger, more stable, and capable of moving quicker.

4. Coordination. Most people that I know have the raw components of what is needed to do a double under, but many can't do it simply due to lack of practice in the coordinated movement. It teaches you how to move better as one unit, plain and simple.

5. Midline stabilization. Haven't watched the video yet, but I've been doing double unders since I was in elementary (Japanese PE classes feature jump rope quite a bit), and one thing that I noticed over the years of doing them is that my abdominal muscles were definitely working in order to maintain a good strong position that would set me up for the next rep. If your body is broken and not connected from head to toe, you're going to trip up pretty quickly and have a hard time stringing reps together. Double unders teach you to quickly stabilize your midline during dynamic movement, something that has plenty of real life application.

The list could go on and on. For some, double unders are extremely easy, and for others, it is a huge challenge that they need to work hard to overcome. Either way, there is a lot of benefit from it even if we don't use that exact movement in real life all of the time.

Tim, one other interesting tid bit about double-unders. In the 2010 games, Mikko Salo had trouble with double-unders. In months following the games, he was interviewed and said that he went back to Finland and practiced double-unders 30 minutes every day. As a result, not only did his double-unders get better but so did his running and box jumps. I wish I could point you to the video, but I thought it was pretty interesting.

I wish I could do more than two at a time. Looking forward to the rest of this series.

I have a theory and it is called the lost art of jump roping. I train a group of high school kids and also a group of older woman aka a mom's club and surprisingly the mom's are better at jump roping (singles that is). Some of these kids are the worst jump ropers I've ever seen but i digress.

The beauty of the double under when properly executed as stated in the video is that it creates triple extension. In a sense you are teaching yourself that position, but it goes both ways because if you do it incorrectly you are reinforcing errant form (the muted or unopened hip). If you watch the classic Buddy Lee video on the double under, you will see that the jump is the same as a single but just with a bit more "pop" to it. I love this video because it ties everything together. The hollow position, the double under, triple extension, etc. If that isn't functional I don't know what is.

My favorite part of the video is when paoli talks about crossfit helping out your sport or crossfit pulling things from outside to make you a better crossfit athlete. This open cell membrane, two way street concept of fitness makes for some interesting adaptations.

The (stable neutral spine) position that Kelly and Carl are demonstrating allows for most efficient force production over the longest time while minimizing the chance for injury. It is a functional target. By getting as close to it as we can, in as wide a variety of challenges as possible, as consistently as possible, we maximize performance.

We went heavy on day 2 of the Coaches Prep Seminar this past Thursday, and as I got closer to my 1RM in the clean and jerk EC pointed out that I was hyperextending my lumbar spine when punching the weight overhead, and that to do so was putting my low back at risk. Perfect observation on her part.

In my case core stability drills, postural awareness and improved ab strength won't be enough to help me maintain that locked and loaded hollow position until I get my lats and teres major stretched out and improve my shoulder flexibility. Decades of less-than-full-ROM pullups and arching handstands have shortened muscles and fascia and reinforced a movement pattern that blocks me out of a more efficient and safe overhead support position. This makes other muscles and structures work much harder than necessary, hindering my performance and progress on a wide variety of functional movements while simultaneously exposing my low back and shoulders to substantially increased loads and risks.

The goal of achieving and mastering "The Position" is indeed universal and the components of mastery are the same for all, but the order and priorities for obtaining each of the necessary components will differ depending on the challenges faced by each athlete.

Dane,
Thanks for writing. I can picture exactly what you're talking about on going overhead. In my case, I can manage it pretty well up top, but in those squats I hadn't grasped just how thoroughly one has to turn it on, from the ribs, abs, lower back, rear end, and so on.

It's taken this long to respond because I too was at a seminar this weekend, Brian Mackenzie's Endurance cert. You won't be surprised to hear that this hollow applies to running as well. He said the position takes a while to learn and develop; the hollow rockers we hit on the ground, when truly and properly assembled, were absolutely brutal.

For the foreseeable future, we're going to be spending as much effort maintaining 'The Position' as we are in whatever we're deadlifting or squatting or running - or anything.

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